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    <meta charset="UTF-8">
    <title>Title</title>
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<span>Hello world!</span>
<ul id="nav">
    <li>电影</li>
    <li>综艺
        <ul>
            <li>跑男</li>
            <li>爸爸</li>
            <li>极限</li>
        </ul>
    </li>
    <li>剧集</li>
</ul>
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